Henry loewenberg



combined.

dinited grates ;ieatrnt Gtilfiite HENRY LOEWENBERG, OF NEW YORK, N. Y.,ASSIGNOR TO MODENA HAT COMPANY.

Letters Patent No. 101,142, dated March 22, 1870.

IMPROVEMENT IN DIES FOR THE MANUFACTURE OF IMI'I'ATION-STRAW GOODS TheSchedule referred to in these Letters Patent and making part of the sameTo all whom it may concern.-

Be it known that I, HENRY Lonwnxnnne, of the city, county and State ofNew York, have invented new and useful Dies for the lilanuiaetureofLmitation-Straw Goods; and that the following is a full, clear, andex-,

act description of my invent-ion.

My invention consists of a compound metal-faced die, composed of a bodyunited to a metal skin, which is a direct counterpart of the surface ofan article 'of natural straw, of the form and size of the imitation-.

straw goods to be manufactured, so that said die possesses theadvantages of a die of solid metal, and possesses the propertyofimparting to the surface of imi-' tation goods against which it ispressed a surface which is a substantial fiw smile of the originalnatural-straw article.

My invention consists further, of the combination of the said die with acounter-die, to support the material while it is pressed by the die.

In order that my invention maybe fully understotal, I will proceed todescribe the best mode with which I am acquainted of producing my newdies.

I procure an article of natural straw, of the form and size of theimitation articles to be manufactured by the use of my dies, as, forexample, a natural Leghorn-straw bonnet, or I procure the natuml-strawbraid and have it made into the desired article in the usual manner. Tothe interior of this article is ap plied a resinous preparation,composed of beeswax, or

of equal quantities of weight of gutta-percha and beeswax, which aresimmered together at about the boiling-point of the mixture until theyare thoroughly This preparation is applied while hot by means of abrush, and in'such quantities as to penetrate the straw article. Theobject of this application is to render the interior of the strawpractically impenetrable by acid or alkaline solutions, and to stiffenthe article.

To the exterior of the article is applied a resinous varnish, and thevarnish which is preferred for this purpose iseither a solution ofgum-ammoniacin alcohol, in the proportions of one pound of the gum tothree pounds of alcohol of ninety-five per cent, or the flocking varnishused by manufacturers of wall-paper and composed of linseed-oil,gum-copal, Burgundy pitch, and spirits of turpentine. This varnish isapplied with a brush, and should be sutficieutly liquid to strike intothe article until it meets the composition previously applied to theinterior, so that all the pores of the article are filled up with aneutral substance. If the flocking varnish, when purchased from themanufacturer, is not sufficiently liquid for this purpose, itsconsistency should be reduced by adding spirits of turpentine to it. I

The purpose of filling the pores of the straw is to prevent acid oralkaline solutions from penetrating the substance of the straw, and thevarnish also serves to retain a coating of plumbago when this materialis used to make the surface a conductor of electricity.

While the exterior of the varnished articlejs still sticky, powderedblack-lead or plumbago is applied to y it and brushed evenly andthoroughly, so as to prodnce a surface that will conduct electricitywithout materially effecting the form of the surface of the straw.

Then the prepared article is stayed :in the form of the die by stickingit fast to a stay of sheet-brass, by warming the composition on itsinterior. The sheet brass stay should approximate in form to that of.the interior of the article, and should be coated with beeswax, or withthe composition of gutta-percha and beeswax. The prepared article sostayed is immersed in a suitable electrotyping-bath, is connected with abattery, and is electrot-yped with copper in the usual manner, whichbeing well known does not'require a detailed description. 1

When the electrotype has formed upon the article of the desiredthickness, say, aboutone-tbrtieth of an inch, the article with theelectrotype upon it is removed from the bath, and the article isstripped out of the electrotype, which has the form of a shell whoseinterior is a counterpart in size, surface, and form of thenatural-straw article upon which it has been deposited.

The shell is tinned upon its exterior by being heated hot enough to melttin-foil, which is applied to it in the usual manner practiced inpreparing electrotypes for backing, or the back of the shell may betinned by the use of a tinsmiths copper in the usual way practiced bytinsmiths, and the shell is then backed by casting melted type-metalupon it in the usual manner practised by electrotypers, the face of. theshell being first rubbed with clay to prevent the accidental adhesion oftype-metal to it.

This backing operation may be efiected in several ways; thus, the shellmay be placed upon a table and surrounded by a boxor mold of therequired form of the die, and then melted type-metal may be poured intothe mold, care being taken, as is customary in such operations, toprevent the shell from rising in the mold; or the shell may be supportedduring the operation upon a bed of dry clay, well rammed, or of dryplaster of Paris; or the shell may be supported upon a core oftype-metal, formed by casting typemetal into the shell, which should bepreviously rubbed with clay to prevent adhesion; and if necessary theexterior of the shell may be supported during the casting of the core bya mold-board, of wood, or by a bedding of dry clay or dry plaster, wellrammed.

The type-metal unites with the tinned surface of the the purpose.

shell and completes the die, which, when cold, is removed from the moldand dressed up in a planer for planing metals, so that its bottom istrue and level, and its exterior is of the exact size required.

The die thus formed, when cleansed of theclay, is an article having atone side a skin whose surface is a substantial counterpart in metal ofthe natural-straw article which has served as a pattern, while the bodyof the die fits all the inequalities of the copper skin that forms itsmetallic surface, however minute such inequalities may be, is firmlyunited to this skin, so that the die is for all practical purposes assolid as if made of one piece, and forms an equable support for. suchskin, however its surface may vary from a plane.

The die thus produced is used for manufacturing imitation-straw goods,in connection with a counterdie, and the said counter die may beprepared by pouring melted typemetal into the cavity of the die afterthe surface thereof has been rubbed by hand with fine tion of thesurfaceof the type-metal of the die as may be exposed to t e action ofsuch melted type metal is prevented from adhering thereto by being firstcoated with paper-clay or some other material that will answer The massof type-metal is permitted to cool, and then has its base dressed ofl'true in a planer, after which its surface is reduced by filing orscraping, sufficiently to permit of the insertion between it and the dieof one of the articles to be pressed, and also of a thin sheet of Indiarubber.

The rubber used should be vulcanized, and about one-eighth of an inch inthickness, and the extent of reduction of the counter-die is determinedby trials,

consisting in inserting it with the rubber and an article upon it intothe die, after the latter has been cleansed of the clay, and cuttingaway the surface progressively until an equal bearing is obtained overthe entire surface of the article to be pressed.

If the above operations have been carefully performed, the two articles,die and counter-die, thereby produced, will constitute a set of diessuitable for pressing material into the form of the natural-strawarticle, and for imparting to the said material a surface which issubstantially a fac smile of that article.

Having thus described my new die and the combination of it with thecounter-die, I declare that I do not claim every kind of straw-surfacedmetal die,- nor every straw-surfaced metal die made in part by theelectrotype process, because I am aware that dies have been engraved sothat their surfaces resembled that of straw goods; also, that dies' havebeen made by electrotyping casts or molds of straw goods, and thentinning the'electrotypes and casting type-metal upon them; andI am awarethat a description exists of dies made by electrotyping straw goods andcasting melted-zinc and brass upouthe electrotypes. As the first andsecond of the above kind of strawfaced dies are not direct counterpartsof the'na'tural straw, but are either copies of it made by eye orcounterparts of casts or molds, and consequently have all theimperfections of such casts or molds, I do not include them in my claimof invention; and as, in strawfaced dies of the third kind, (if everthey were made,)

the skin and body are not united, I do not include them in my claim. Ifurther declare that I am aware that strawaced dies of one of the abovekinds have been used in combination with a counter-die; Itherefore donot claim the combination of every kind of straw-faced die with acounter-die; but

What I claim as myinventiomand desire to secure by Letters Patent, is rThe compound metal-faced straw-surface die, composed of a body united toa ruetal skin which is a direct counterpart of an article of naturalstraw, substantially as before described.

Also, the combination of the said compound metal-v faced straw-surfacedie with a counter-die, substantiall y as before described.

In testimony whereof I have hereto set my hand this 6th day of March, A.D. 1867.

HENRY LOEWENBERG;

Witnesses:

J no. D. Puma, D. P. Gown.

